A broadcast receiving system which simultaneously supports time-delayed viewing and recording/reproduction. In the broadcast receiving system, blocks are discontinuously arranged in a circular buffer to rapidly implement time-delayed viewing of a channel and recording/reproduction of another channel at the same time. To do so, circular buffer blocks are discontinuously arranged on a disk surface in a time-delayed viewing mode. If the time-delayed viewing mode is performed simultaneously with a recording/reproduction mode, video streams for time-delayed viewing are recorded in free blocks nearest to blocks in which video streams of a channel to be recorded are recorded or from which video streams of a channel to be reproduced are reproduced. Therefore, two or more modes can be performed effectively and simultaneously.
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16. A video stream processing method in a broadcast receiving system, the video stream processing method comprising:
recording a video stream in free blocks of a disk recording area or reading a recorded video stream recorded in the disk recording area; and
using a processor to assign free blocks nearest to the recorded or reproduced free blocks as logical blocks in a circular buffer,
wherein physical blocks are indicated to be free blocks in control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
30. A broadcast receiving system, comprising:
a hard disk drive having a hard disk as a recording medium, the recording medium having control information for recording an input signal and reproducing recorded information;
a controller which records a video stream in physical free blocks of the recording medium or reads a recorded video stream recorded on the recording medium and assigns physical free blocks nearest to the recorded or reproduced physical free blocks as logical circular buffer blocks based on the control information,
wherein physical blocks are indicated to be free blocks in the control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
19. A broadcast receiving system, comprising:
a hard disk drive having a hard disk as a recording medium, the recording medium having control information for recording an input signal and reproducing recorded information; and
a controller which assigns physically discontinuous free blocks in a disk recording area to sequential logical blocks in a circular buffer, based upon the control information in response to a time-delayed viewing mode being selected, and which records video streams for time-delayed viewing in the assigned circular buffer blocks,
wherein physical blocks are indicated to be free blocks in the control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
15. A video stream processing method in a broadcast receiving system for time-delayed viewing, which includes a hard disk drive having control information required for recording an input signal and reproducing recorded information in a predetermined area, the video stream processing method comprising:
reading blocks to be reproduced based on the control information;
using a processor to assign free blocks nearest to the reproduced free blocks as logical blocks in a circular buffer; and
recording video streams for time-delayed viewing in the assigned circular buffer blocks,
wherein physical blocks are indicated to be free blocks in the control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
1. A video stream processing method in a broadcast receiving system for time-delayed viewing, which includes disks having control information required for recording an input signal and reproducing recorded information recorded and a drive for driving the disks, the video stream processing method comprising:
using a processor to assign physically discontinuous free blocks in a disk recording area to sequential logical blocks in a circular buffer, based on the control information when a time-delayed viewing mode is selected; and
recording video streams for time-delayed viewing in the assigned circular buffer blocks,
wherein physical blocks are indicated to be free blocks in the control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
14. A video stream processing method in a broadcast receiving system for time-delayed viewing, which includes a hard disk drive having control information required for recording an input signal and reproducing recorded information in a predetermined area, the video stream processing method comprising:
using a processor to assign free blocks of a recording disk area;
recording video streams of a channel to be recorded in the assigned free blocks;
assigning free blocks nearest to the recorded free blocks as logical blocks in a circular buffer; and
recording the video streams for time-delayed viewing in the assigned circular buffer blocks,
wherein physical blocks are indicated to be free blocks in the control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
17. A non-transitory recording medium in a broadcast receiving system having a hard disk drive, the recording medium comprising:
a video stream storing area which records video streams, comprising:
video stream blocks which are physically discontinuously arranged and assigned sequentially within a circular buffer, and which are used to record video streams for time-delayed viewing; and
free blocks which are logically assignable to the circular buffer, or which record other video streams during a mode other than a time-delayed viewing mode; and
a control information area which stores control information relating to the video stream storing area,
wherein the video stream blocks are arranged physically discontinuously based on the control information stored in the control information area,
wherein physical blocks are indicated to be free blocks in the control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
13. A video stream processing method in a broadcast receiving system for time-delayed viewing, which includes a hard disk drive having control information required for recording an input signal and reproducing recorded information in a predetermined area, the video stream processing method comprising:
using a processor to assign physically discontinuous free blocks in a disk recording area to sequential logical blocks in a circular buffer and recording video streams for time-delayed viewing in the assigned circular buffer blocks, based on the control information when a time-delayed viewing mode is selected; and
reading blocks to be reproduced based on the control information, assigning free blocks nearest to the reproduced free blocks as the circular buffer blocks, and recording the video streams for time-delayed viewing in the assigned circular buffer blocks, when a reproduction mode is selected together with the time-delayed viewing mode,
wherein physical blocks are indicated to be free blocks in the control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
8. A video stream processing method in a broadcast receiving system for time-delayed viewing, which includes a hard disk drive having control information required for recording an input signal and reproducing recorded information recorded in a predetermined area, the video stream processing method comprising:
using a processor to assign physically discontinuous free blocks in a disk recording area to sequential logical blocks in a circular buffer and recording video streams for time-delayed viewing in the assigned circular buffer blocks, based on the control information when a time-delayed viewing mode is selected; and
assigning free blocks of the disk recording area and recording video streams of a channel to be recorded in the assigned physically discontinuous free blocks when a recording mode is selected during the time-delayed viewing mode, assigning free blocks nearest to the recorded free blocks as the circular buffer blocks, and recording the video streams for time-delayed viewing in the assigned circular buffer blocks,
wherein physical blocks are indicated to be free blocks in the control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
11. A video stream processing method in a broadcast receiving system for time-delayed viewing, which includes a hard disk drive having control information required for recording an input signal and reproducing recorded information recorded in a predetermined area, the video stream processing method comprising:
using a processor to assign physically discontinuous free blocks in a disk recording area to sequential logical blocks in a circular buffer and recording video streams for time-delayed viewing in the assigned circular buffer blocks, based on the control information when a time-delayed viewing mode is selected;
assigning free blocks of the disk recording area, recording video streams of a channel to be recorded in the assigned physically discontinuous free blocks, assigning free blocks nearest to the recorded free blocks as the circular buffer blocks, and recording video streams for time-delayed viewing in the assigned circular buffer blocks, when a recording mode is selected together with the time-delayed viewing mode; and
reading free blocks to be reproduced based on the control information, assigning free blocks nearest to the reproduced free blocks as the circular buffer blocks, and recording the video streams for time-delayed viewing in the assigned circular buffer blocks, when a reproduction mode is selected together with the time-delayed viewing mode,
wherein physical blocks are indicated to be free blocks in the control information, and
wherein the control information comprises file attribute information, file assignment information, free block information for each track, and circular buffer block information.
2. The video stream processing method of
3. The video stream processing method of
4. The video stream processing method of
recovering the circular buffer blocks to the free blocks when the broadcast receiving system is initialized.
5. The video stream processing method of
6. The video stream processing method of
7. The video stream processing method of
9. The video stream processing method of
10. The video stream processing method of
12. The video stream processing method of
18. The recording medium of
file attribute information;
file assignment information;
free block information which manage the free blocks for each track of the recording medium; and
circular block information which manage the circular buffer blocks.
20. The broadcast receiving system of
a broadcast signal receiver comprising:
a first radio frequency tuner which receives an external broadcast signal,
a second radio frequency tuner which receives an external analog broadcast signal,
a video compressor which converts the received analog signal to a digital signal and compresses the digital signal, and
a selector which selectively enables transmission of the external digital broadcast signal and the compressed digital signal;
a random access memory which temporarily stores the selectively transmitted external digital broadcast signal and the compressed digital signal from the selector prior to recording on and subsequent to reading from the recording medium; and
a video recovery unit which restores the video streams read from the recording medium and temporarily stored in the random access memory to original signals.
21. The broadcast receiving system of
an input device which enables simultaneous operation of the time-delayed viewing mode and a recording mode;
wherein the controller assigns free blocks of the recording medium, records the video streams of a channel to be recorded in the assigned free blocks in response to the selection of the simultaneous operation of the time-delayed and recording modes, assigns free blocks nearest to the recorded free blocks as circular buffer blocks, and records the video streams for time-delayed viewing in the assigned circular buffer blocks.
22. The broadcast receiving system of
an input device which enables simultaneous selection of the time-delayed viewing mode and a reproduction mode;
wherein the controller reads blocks to be reproduced based on the control information, assigns free blocks nearest to the reproduced free blocks as the circular buffer blocks, and records the video streams for time-delayed viewing in the assigned circular buffer blocks, in response to the selection of the simultaneous operation of the time-delayed and reproduction modes.
23. The broadcast receiving system of
24. The broadcast receiving system of
a control unit which controls the hard disk drive;
and an expander which expands the hard disk drive.
25. The broadcast receiving system of
a read-only memory which stores control program data to control the random access memory and the hard disk drive; and
a second random access memory which temporarily stores data during a control operation of the controller.
26. The broadcast receiving system of
a random access memory which temporarily stores the video streams prior to recording on and subsequent to reading from the recording medium, wherein the random access memory comprises:
a control information copy area in which the control information is copied during system initialization of the broadcast receiving system,
a circular buffer pointer area having a pointer array which points to the circular buffer blocks, and
a video stream buffer area which buffers blocks of the video streams; and
a video recovery unit which restores the video streams read from the recording medium and temporarily stored in the random access memory to original signals.
27. The broadcast receiving system of
28. The broadcast receiving system of
29. The broadcast receiving system of
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This application claims priority to an application entitled “Video Stream Processing Method for Time-Delayed Viewing” filed in the Korean Industrial Property Office on Oct. 8, 1999 and assigned Serial No. 99-43407, the contents of which are hereby incorporated by reference.
1. Field of the Invention
The present invention relates generally to a broadcast receiving system capable of concurrently supporting time-delayed viewing and recording/reproduction of a broadcast signal, and in particular, to a video stream processing method in which a circular buffer, assigned on a recording medium surface for time-delayed viewing, is constituted of discontinuous blocks.
2. Description of the Related Art
Due to its advantages of random access, high data transmission rate, low price, and large capacity as compared to other auxiliary storage devices, a hard disk drive (HDD), which is an auxiliary storage device of a computer system, is used as a random access storage device for a broadcast receiving system.
Such a broadcast receiving system enables simultaneous recording/reproduction with time-delayed viewing of broadcast video streams by controlling buffering of the video streams input/output to/from the HDD.
A description will hereinbelow be given of a method of arranging video streams on a hard disk recording area that is a recording medium in the broadcast receiving system.
Referring to
When video streams are discontinuously arranged as shown in
The management of the hard disk area in the form of a circular buffer as shown in
A broadcast receiving system, if it employs the discontinuous video file arranging scheme shown in
It is, therefore, an object of the present invention to provide a video stream processing method in which circular buffer blocks are arranged discontinuously in such a way that time-delayed viewing of one channel can be implemented simultaneously with recording/reproduction of another channel.
Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
The time-delayed viewing mode is one in which the user can operate a recording and/or reproducing device so that the broadcast signal is recorded simultaneously within a temporary buffer (a buffer for holding the received content for a limited period of time, e.g., thirty minutes), while viewing prerecorded contents. The temporary buffer can later be retrieved for viewing prerecorded contents using rewind, pause and fast-forward operations. If the time-delayed viewing mode is inactive, no content will be recorded and only real-time viewing is possible.
The recording mode is activated when a user-scheduled event for recording a certain program channel at a certain period of time has met the recording start time. The reproducing mode is activated when a user-scheduled event for reproducing a recorded content (performed in the recording mode) has met the reproducing start time. The reproducing mode is useful for presenting the content to different terminals (TVs) for multi-user viewing or to VCRs for backup purposes. These modes are all independent from the time-delayed viewing, which operates on a temporary basis at a designated terminal. All of the different modes can be carried out simultaneously with different input/output devices, with all of the contents being stored in a shared disk storage system.
To achieve the above and other objects and advantages of the present invention, there is provided a video stream processing method in a broadcast receiving system for time-delayed viewing, which includes a hard disk drive having control information required for recording an input signal and reproducing recorded information recorded in a predetermined area. When a time-delayed viewing mode is selected, free blocks are sequentially assigned as discontinuous circular buffer blocks in a disk recording area and video streams for time-delayed viewing are recorded in the assigned circular buffer blocks, based on the control information. When a recording mode is selected together with the time-delayed viewing mode, free blocks of the disk recording area are assigned, video streams of a channel to be recorded are recorded in the assigned free blocks, free blocks nearest to the recorded free blocks are assigned as circular buffer blocks, and video streams for time-delayed viewing are recorded in the assigned circular buffer blocks. When a reproduction mode is selected together with the time-delayed viewing mode, blocks to be reproduced are read based on the control information, free blocks nearest to the reproduced free blocks are assigned as circular buffer blocks, and video streams for time-delayed viewing are recorded in the assigned circular buffer blocks.
The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:
A preferred embodiment of the present invention will be described hereinbelow with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.
Referring to
The random access storage device 30 records a digital video stream received from the broadcast signal receiver 10 in a recording area of a hard disk under the control of a controller 40 and reads the stored video stream. This random access storage device 30 includes an HDD 34 and the dual port RAM 32. The HDD 34 comprises a plurality of hard disks for permanently storing a digital video stream, a controller for controlling the operation of the HDD 34, and an expander (IEEE 1394 interface) for expanding the HDD 34. The dual port RAM 32 includes at least a video stream buffer for temporarily storing a digital video stream.
A video recoverer 50 recovers a video stream received from the random access storage device 30 through a system bus to an original signal and outputs the recovered video stream to a TV receiver 90.
The controller 40 has a ROM for storing control program data to control the random access storage device 30 and the broadcast signal receiver 10 and a RAM for temporarily storing data generated during a control operation.
A remote controller 60, having a plurality of control keys for system control, generates data corresponding to key input and outputs the data to the controller 40. The control keys include “pause”, “rewind”, “rapid search”, and “time-delayed view”.
A computer interface 70 interfaces signals between the broadcast receiving system according to the embodiment of the present invention and a computer. A timer 80 generates time information so that the broadcast receiving system can implement automatic recording.
Referring to the layout indicated in
The video stream storing area 38 comprises circular buffer areas a, b, and c, free blocks d, and blocks e in which video streams have been recorded in a mode other than a time-delayed viewing mode. The circular buffer areas a, b, and c do not always include successive blocks but may be arranged discontinuously in a disk area in a physical sense, while they are managed continuously in a logical sense. All blocks in the video stream storing area 38 are the same size. One block can include a plurality of consecutive sectors physically and is accessed by one disk operation (read/write) at one time.
Referring to the layout shown in
A method of discontinuously arranging blocks in a circular buffer area will be described with reference to
In the embodiment of the present invention, free blocks are assigned for video streams in a disk recording area of the HDD 34 in an ascending order of tracks/sectors. Generally, tracks concentrically arranged on a disk are numbered from the outer-most circumference to the innermost circumference. After free blocks of the last track are assigned in this manner, the assignment restarts with the first track so that free blocks are assigned in the form of a circle. In case video streams of different channels are recorded concurrently, blocks are assigned interleavedly for each video stream to thereby minimize the movement of a head. Thus, the present broadcast receiving system can simultaneously record video streams of video channels. For analog TV broadcasting, multiple receivers are used, whereas for digital TV broadcasting, a single multiplexed receiver will suffice.
Referring to
Then, the controller 40 is placed in a standby mode and determines whether a video stream processing mode is set in step 130. The video stream processing mode refers to a mode for processing video streams received/transmitted through channels or video streams reproduced from a disk, including a time-delayed viewing mode, a recording mode, a reproduction mode, and a time-delayed viewing & recording/reproduction simultaneous mode. Therefore, if it is determined that a user has input a command to implement one of the modes in step 130, the controller 40 performs a video stream processing sub-routine in the way shown in
The video stream processing sub-routine will be described in detail with reference to
If the controller 40 considers that the current system mode is set to a time-delayed viewing mode in step 200, it determines whether the time-delayed viewing mode is to be implemented together with a recording or reproduction mode in steps 210 and 220 by checking user input of a command for a corresponding mode through the remote controller 60. If only the time-delayed viewing mode has been selected, the controller 40 assigns free blocks as circular buffer blocks referring to the control information in the control information copy area I of the dual port RAM 32 in step 230. The free blocks are assigned in a track/sector number ascending order as stated before. The term “circular buffer block” as used herein is defined as a free block assigned to form a circular buffer and record a video stream for time-delayed viewing therein.
In step 240, the controller 40 records digital video streams received from the broadcasting signal receiver 10 in the assigned circular buffer blocks. The controller 240 sets the pointer of the write point W to point to the last assigned circular buffer block in step 250 and changes the previously assigned circular buffer blocks to free blocks in step 260. The controller 240 updates the control information in the control information copy area I of the dual port RAM 32 and returns to the main loop shown in
Now there will be given a description of simultaneous implementation of time-delayed viewing and (reserved) recording/reproduction.
When a recording mode is selected during the time-delayed viewing mode or both modes are selected at the same time, the controller 40 assigns free blocks based on control information in step 300 and records video streams of a corresponding channel in the assigned free blocks in step 310. In step 320, the controller 40 assigns free blocks nearest to the recorded free blocks as circular buffer blocks. The controller 40 records video streams for time-delayed viewing in the assigned circular buffer blocks in step 330. The “free blocks nearest to the previous free blocks” may be on the same track or in the nearest track. This aims at minimization of track search time by minimizing head movement. If free blocks in an adjacent track are assigned, the track is preferably located in the head moving direction.
The controller 40 sets the pointer of the write point W to point the last assigned circular buffer block in step 340 and changes the previously assigned circular buffer blocks to free blocks in step 260. The controller 40 updates the control information in the control information copy area (I) of the dual port RAM 32 in step 270 and repeatedly performs steps 300 to 340 and steps 260 and 270 to concurrently implement the recording and time-delayed viewing modes until at least one of the time-delayed viewing mode and the recording mode is released. Accordingly, the nearest free blocks to free blocks selected for recording are assigned as circular buffer blocks so that the moving time of the head for track search can be reduced.
When a reproduction mode is selected during the time-delayed viewing mode or both modes are selected at the same time, the controller 40 reads blocks to be reproduced based on control information in step 400 and assigns free blocks nearest to the reproduced free blocks as circular buffer blocks in step 410 to minimize track search time through minimization of head movement. The controller 40 records video streams for time-delayed viewing in the assigned circular buffer blocks in step 420 and sets the pointer of the write point W to point the last assigned circular buffer block in step 430. The controller 40 changes the previously assigned circular buffer blocks to the free blocks in step 260, updates the control information in the control information copy area (I) of the dual port RAM 32 in step 270, and returns to the main loop. Accordingly, the nearest free blocks to the free blocks read for reproduction are assigned as circular buffer blocks so that the moving time of the head for track search can be reduced. Meanwhile, if a command to release the current mode has been received from the user in the video stream processing mode, the controller 40 ends the control operation shown in
In accordance with the present invention, head movement can be reduced by assigning circular buffer blocks for time-delayed viewing in a track near to video stream blocks that are being recorded/reproduced when a time-delayed viewing mode is performed simultaneously with a recording/reproduction mode.
While the invention has been shown and described with reference to a certain preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Patent | Priority | Assignee | Title |
10032478, | Jul 14 2014 | NFL Enterprises LLC | Video replay systems and methods |
11226852, | Nov 25 2016 | GENETEC INC | System for inter-process communication |
7996875, | May 20 2008 | Microsoft Technology Licensing, LLC | Adaptive timeshift service |
8578431, | May 20 2008 | Microsoft Technology Licensing, LLC | Adaptive timeshift service |
9084017, | Nov 13 2001 | Sky CP Limited | Receivers for television signals |
9113209, | Nov 13 2001 | Sky CP Limited | Receivers for television signals |
9124935, | Nov 13 2001 | Sky CP Limited | Receivers for television signals |
9721495, | Feb 27 2013 | E Ink Corporation | Methods for driving electro-optic displays |
9923969, | Aug 05 2015 | FUTUREWEI TECHNOLOGIES, INC | Large-scale storage and retrieval of data with well-bounded life |
Patent | Priority | Assignee | Title |
5317739, | Mar 30 1992 | INTERNATIONAL BUSINESS MACHINES CORPORATION A CORP OF NEW YORK | Method and apparatus for coupling data processing systems |
5371551, | Oct 29 1992 | LOGAN, BERNICE C , TRUSTEE OF THE JAMES D LOGAN AND KERRY M LOGAN FAMILY TRUST | Time delayed digital video system using concurrent recording and playback |
5765200, | Jun 07 1995 | International Business Machines Corporation | Logical positioning within a storage device by a storage controller |
5771331, | Sep 05 1994 | Sony Corporation | Reproduction of information using a ring buffer with read and write pointers separated from each other by substantially half of the total ring buffer capacity |
5881041, | Dec 27 1996 | Pioneer Electronic Corporation | Apparatus for recording and reproducing information |
5884284, | Mar 09 1995 | COMCAST MO GROUP, INC | Telecommunication user account management system and method |
6009231, | Sep 05 1994 | Sony Corporation | Reproduction of information using a ring buffer with read and write pointers separated from each other by substantially half of the total ring buffer capacity |
6233389, | Jul 30 1998 | TIVO SOLUTIONS INC | Multimedia time warping system |
6633516, | Jun 21 2000 | Sony Corporation | ZCAV optical and method for accessing thereof |
7068921, | Jul 28 1999 | Samsung Electronics Co., Ltd. | Method of arranging divided recording area segments of recording medium in broadcast receiving system |
20030007079, | |||
20050244138, | |||
CN1208891, | |||
JP10199213, | |||
JP11053235, | |||
JP4095271, | |||
JP6349197, | |||
JP8256305, | |||
JP9270186, |
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